Method for embossing repeated patterns in strip material,preferably metal strip and means for carrying out the method



K. G. JONASON 3,465,568 SING REPEATED PATTERNS IN STRIP Sept. 9, 1969METHOD FOR EMBOS MATERIAL, PREFERABLY METAL STRIP AND MEANS FOR CARRYINGOUT THE METHOD 2 Sheets-Sheet 1 Filed Feb. 9, 1967 Sept. 9, 1969 K. G.JONASON 2 Sheets-Sheet 2 Filed Feb. 9. 1967 United States Patent M3,465,568 METHOD FOR EMBOSSING REPEATED PATTERNS IN STRIP MATERIAL,PREFERABLY METAL STRIP AND MEANS FOR CARRYING OUT THE METHOD Karl GunnarJonason, Vasteras, Sweden, assignor to Aktiebolaget SvenskaMetallverken, Vasteras, Sweden Filed Feb. 9, 1967, Ser. No. 614,926Claims priority, application Sweden, Feb. 11, 1966, 1,784/ 66 Int. Cl.B21d 28/00, 53/ 00, 43/28 US. Cl. 72-338 19 Claims ABSTRACT OF THEDISCLOSURE An apparatus and method which enable patterns to be embossedby inflating means in successive portions of a material web. Theembossing operation is facilitated by a communicating passage which ispressed out in the web portion immediately following the web portionbeing embossed, so that when said two portions are separated and openingis exposed in the said following portion, for the nozzle of saidinflating means.

BACKGROUND The present invention relates to a method for embossingrepeated patterns in strip material, preferably metal strip, at suitabletemperatures, at least two material webs in superimposed relationshipbeing advanced intermittently and subjected therebetween to the actionof a pressure medium, in predetermined zones during the repeatedstoppages of the Web material, the said pressure medium pressing out thedesired pattern in relief, whereupon the work piece on which the patternhas been embossed is separated and the working sequence repeated.

It is previously known to emboss patterns in web or sheet-like materialby means of a pressure medium, usually oil or air, whereby substantiallythe same result is obtained as when embossing by means of mechanicalsheet-metal presses. The method has gained particular interest in theembossing of repeated patterns in mass produced articles made from metalstrip or metal plate, e.g. heat exchangers. The usual practice is toarrange a number of material webs, normally two, in superimposedrelationship and inject the pressure medium between the webs so thatcertain predetermined zones, forming a pattern, are distended in eitherof the two webs or in both of said webs. The embossing operation iseffected intermittently for each pattern, by forcing the webs apart atsome suitable point along the edges of the same and injecting thepressure medium between the webs at this point. The pressure mediumforces its way through flow paths which have been previously disposedbetween the webs, and presses out relief patterns in the walls alongsaid path, while remaining zones of the said webs are sealed oif fromone another and prevent the pressure medium from entering therein.Normally only one pattern is embossed at a time, it being necessary tocut-ofi' the supply of pressure medium to the following portions of thecontinuous webs, a procedure which is eifected by means of so-calledholder plates which clamp the Webs together at some suitable point inthe direction of feed, behind the embossing zone. The pressure isrelieved after each embossing operation, whereupon the embossed zone ofthe web is severed transversely of the webs, and removed so as toprepare a place for the intermittently advanced web so that the nextpattern can be embossed. However, before the next pattern can beembossed, an opening must be made manually between the two webs.

3,465,568 Patented Sept. 9, 1969 This latter operation constitutes thetrue obstacle in providing for a rapid and continuous embossing sequenceand consequently it is the object of the invention to eliminate thisdisadvantage.

In accordance herewith, the invention is mainly characterized in that apassage communicating with the adjacent, unembossed portion of the webis formed in conjunction with the step of embossing a pattern on thepreceding web portion, and that each embossed Web portion is separatedfrom the web material, the communicating passage being parted inconjunction therewith so that an opening is formed in the adjacent Webportion, after which the source of pressure medium is connected to thesaid opening.

The invention also includes an arrangement for carrying out the method,which is mainly characterized by a delay station wherein a determinedportion of the advanced material web is periodically stopped so that itcan be embossed in conformity with the desired pattern, the said stationbeing designed with two opposing surfaces which restrict the extent towhich the material is distended and the shape of the embossed pattern,and by holder means which are capable of being urged against the websand which, at least during the embossing operation, close thepressure-medium communicating passage, leading to said adjacentunembossed portion of the web, and by cutting means movably arranged infront of said station and intended to cut embossed, finished portions ofthe web from the portion of the web located at that moment in thestation, said means cutting along a line which crosses the communicationpassage at a desired position between the ends thereof so that anopening is formed in the portion of the web located in the station, thecut, finished web portions being removed and a nozzle capable of beingconnected to a source of pressure medium being movable into and out ofsealing engagement with said opening.

The invention will be described in greater detail below with referenceto a number of embodiments shown diagrammatically in the accompanyingdrawing, further characterizing features of the invention beingdisclosed in conjunction therewith.

DETAILED DESCRIPTION OF INVENTION FIGURE 1 shows in perspective adiagrammatical view of a machine for carrying out the method accordingto the invention, the said machine having been provided with essentialmeans for effecting a continuous, semior fully automatic embossingoperation when intermittently advancing, for instance, two metal webs ofwhich one is freely arranged upon the other.

FIGURE 2 shows a cross section of an embodiment of an arrangement,included in the machine, to restrict the extent to which the pattern isdistended, as well as a holder plate intended to cut ofi the supply ofpressure medium to the portions of the webs not being embossed.

FIGURE 3 shows a section of a modified embodiment of the arrangementaccording to FIGURE 2.

FIGURE 4 shows a further modification of the arrangement shown inFIGURES 2 and 3.

FIGURE 5 shows in perspective, by way of an example, a gas burner forseparating the embossed portion of the web.

FIGURE 6 shows, in perspective, a view of a modified arrangement, in theform of shears for clipping off the embossed portion of the web.

FIGURE 7 shows diagrammatically a type of screw nozzle adapted to beinserted into an inlet opening formed in the next portion of the Web tobe embossed subsequent to its being advanced into the delay station,said inlet opening being formed in conjunction with the embossing of thepattern in the preceding portion of the Web.

FIGURE 8 shows another alternative of an insertion nozzle, intended forthe same purpose as the nozzle according to FIGURE 7 and provided with asealing means.

FIGURE 9 shows a simplified form of a similar nozzle not provided withspecial sealing means.

FIGURE 10 shows diagrammatically and in perspective a machine whichsubstantially coincides with the machine shown in FIGURE 1 but which issomewhat modified for the purpose of working with webs of material whichhave been previously provided therebetween with the outlines of thepattern to be embossed and joined together.

FIGURE 1 shows a supporting member 1 on which are rotatably mounted twoshafts 3 and 4 each supporting a roll of strips 5 and 6, comprised ofmetal, plastic or the like. Positioned in front of the support 1 is afurther supporting member 7 presenting two vertical posts 8 and 9, ofwhich the first mentioned post 8 is suitably displaceable towards andaway from the post 9 and capable of being locked in an adjustedposition, so that the distance between the two posts can be set inaccordance with the width of the material coiled on the drums 5 and 6.However, there is nothing to prevent the two posts from being stationaryand arranged at a fixed distance apart.

The posts 8 and 9 also form bearing supports for a feeder mechanismwhich, in the illustrated example, has two driven rolls 10 and 11 and abacking roll 11a disposed beneath rolls 10 and 11. The rolls 10, 11 and11a are driven, via a gear 13 and shafts 14, 15 extending therefrom, byan electric motor 12. The motor is adapted to be driven intermittently;this may be effected automatically by programming.

As can be seen from the figure the webs 16 and 17 are uncoiled from thecoils 5 and 6 and passed together, freely positioned one on top of theother, between the guide posts 8 and 9 and between firstly the roll 11aand secondly the two rolls 10 and 11 into an apparatus which ispositioned in front of the rolls and in which the web material isembossed according to the invention.

The apparatus mainly comprises an elevatable die 18 provided with acentrally positioned upwardly projecting support surface 19 on whichdetermined lengths of the intermittently advanced webs 16 and 17 areperiodically stopped, to permit the embossing operation according to theinvention to be carried out. Located above the die 18 is a stationarysolid block 20, provided with a recessed backing surface at 21. Theshoulder 22 formed on each side of the block 20 projects down at theside of the sup port surface 19 which can be made to abut direct againstthe backing surface 21, or alternatively be stopped or fixed at adetermined distance from the same. This can be effected, for instance,by means of distance pieces inserted between the surfaces, or by meansof lugs or shoulders projecting out from one or the other of thesurfaces or from them both.

Since according to the invention, it is intended to utilize the twosurfaces as a means for restricting the extent to which the material isthe relevant web portion or portions 16, 17 to be embossed is distended,several alternative designs in the structure of the two surfaces 19 and21 may be applicable. Thus, in the simplest construction it may be theintention to emboss the portions of the web located in the describedapparatus so that together they obtain a form which may be compared withthe outer contours of a cushion. In this instance the one surface 19 or21, for example, may be provided with a continuous rectangular strip,projecting out from said surface and which is pressed into contact withthe webs 16 and 17, against the reaction of the other surface. Uponejecting a pressure medium in between the portions of the web which havebeen mechanically pressed together in the manner described, the one webportion is urged against the opposing backing or support plane, whereasthe second web portion abuts its own support surface and cannot bedistended. This means that only the one web portion will be embossed.The edge of the above mentioned strip thus defines the outer contour ofthe embossed pattern while at the same time holds the webs sealinglycompressed against each other along its pressure plane, so that thepressure medium can only act within the confines of the strip. Naturallythe strip-frame can be modified to suit the configuration of anyrequired pattern. Further, several strips may be arranged on the supportor backing surface for the purpose of providing a pattern and forsealing the web portions, in the manner disclosed above.

If, on the other hand, it is desired to emboss both portions of the webit is possible to arrange complementary strips of congruent shape onboth surfaces, the two web portions being sealingly compressed togetherby the strips while situated at a distance from their respectivereaction surfaces, and urged into abutment with the latter by thepressure medium According to another alternative one or the other, orboth of the two surfaces may be engraved, as shown with double dottedlines 23 in FIGURE 1, the reaction planes, prior to the embossingoperation, being compressed together with the portions of the web lyingtherebetween. On commencing the embossing operation the material of theweb portions is only pressed out at those positions where the engravingis located, and distends to form the pattern.

In this connection there are two important requirements which must befulfilled to enable the embossing operation to be confined to thoseparticular web portions which are at that instance located in thedescribed apparatus. Thus, the possibility must be found of closing thepath of the pressure medium to subsequent portions of the webs and aninlet path for the pressure medium must be provided, leading to thezones in the Web portions fed into the apparatus, to be embossed. Thefirst requirement can be fulfilled by using a simple holder device,extending transversely across the webs. This may be a separate devicewhich may also be separately operated, or may comprise a strip-likeshoulder located on one or both of said surfaces, 19, 21.

In fulfilling the second requirement an inlet channel for the pressuremedium can be defined by strips positioned on the backing and supportsurfaces, or alteinatively one or both of the said surfaces may beengraved so that the web portions can be parted at this point and thepressure medium nozzle inserted.

To illustrate the aforementioned, reference is made to FIGURES 2 to 4which comprise sections of alternative embodiments of the two surfaces19, 21, taken in the direction in which the webs are advanced.

FIGURE 2 can be said to illustrate the instance where the two webportions 16a and 17a, one superimposed on the other, are to be distendedbetween the die 18 and the block 20 to form a cushion-like object, theweb portions being held in certain spaced relationship leaving a gap 24which is later filled when the pressure medium is injected between theweb portions, via the inlet opening 25 formed during the precedingembossing operation. In this instance the distance between the twosurfaces is maintained by the two shoulders or strips 25a and 26,located on said surfaces. The shoulders or strips form, at the sametime, holder members which prevent the pressure medium from continuingbackwards past the same, i.e. in the opposite direction to which thewebs are being advanced.

On the other hand the section according to FIGURE 2 can be said torepresent alternatively the instance where the two surfaces 19, 21 areeach provided with upwardly projecting, patterning strips ofcomplementary configuration.

FIGURE 3 shows the alternative in which the backing surface 21 isprovided with a tortuous engraving 27, whereas the opposing supportsurface 19 is completely smooth. In this instance the two plane surfacesof the members 19, 21 can be used as holder plates, since on being urgedagainst the portions of webs 16a and 17a lying therebetween theycompress said web portions sealingly over their entire surface, with theexception of the locations in which the said surfaces have beenengraved.

FIGURE 4 shows the alternative in which the two surfaces 19 and 21 areprovided with complementary engravings 28 and 27 respectively, wherebythe two web portions 16a and 17a are distended into the respectiveengravings and provided with embossed patterns.

Returning to the description of FIGURE 1 the first block 20 rests on anunderlying plate or slab 29 through the intermediary of four posts 30,positioned in the four corners of said plate (only two posts being shownin the figure). The posts 30 serve, at the same time, as guides for thevertically movable block 18, which is in turn supported by a hydraulicpiston 31 operated from a hydraulic cylinder 32 which is supplied withhydraulic pressure medium via a delivery conduit 33. Thus, through theintermediary of these arrangements the block 18 can be made to coactWith the block 20, for the purpose of carrying out some of thealternative functions, described very generally above, in conjunctionwith embossing a pattern, in the described apparatus. Further, inaccordance with the invention arrangements are preferably incorporatedwhich permit programming of the movements of the block 18 in conjunctionwith the intermittent advancing movement of the webs.

FIGURE 1 illustrates a stage in the process wherein a double-layer webportion 35, in which a tort-nous pattern has been embossed, has beenadvanced away from the surfaces 19, 21 on a roller belt 36, .at the sametime as a new, double-layer web portion has been moved into the positionpreviously occupied by the preceding portion, i.e. between the surfaces19 and 21, and securely clamped therebetween.

As can be seen from the figure a communicating passage 37, in accordancewith the most important novel feature of the invention, extendsrearwards up to the edge of the clamped surfaces 19, 21 and terminateswithin the following web portion at that point where pressure mediumwill later be injected for the purpose of embossing the pattern 23 inthe said double-layer web portion situated between the two surfaces 19and 21.

Before the next portion of the web can be embossed, the embossed webportion 35 must be severed from the web and, for instance, placed onstack 38 of finished articles, so that the inlet opening 39 formedduring the preceding embossing operation and leading to the pattern 23can be reached and the source of pressure medium connected thereto. Inpreviously known methods of embossing strip material, in which nocommunication passage according to the above has been formed, theleading web portion, e.g. the portion indicated by the reference numeral35, has been cut off transversely to the longitudinal direction of theweb without leaving an embossed portion. Consequently before connectingup the source of pressure medium it has been necessary to force apartthe compressed webs in order to obtain an opening leading, for instance,to the portion, 23 to be embossed. This task is both difficult and timeconsuming, requires skilled manual effort and, last but not least,constitutes a definite obstruction to automatizing the whole process.

The general object of the invention is thus to eliminate thisobstruction and to enable the process to be made fully automatic.

The problem is solved according to the invention in that the embossedcommunication passage 37 is parted at a convenient point between itsends. Consequently an opening is automatically obtained, into which anozzle for the pressure medium can be inserted without it beingnecessary to create said opening manually. In this way it isalsopossible to coordinate the separating and embossing operation inautomatic coordination, which increases the precision and acceleratesthe production rate.

In the example shown in FIGURE 1, a circular saw 40 is used to part thecommunication passage; the saw being mounted on a beam 41 which isguided for movement by two guides 42 and 43 positioned in a frame 44.The circular saw is driven via a suitable form of transmission means(not shown) by an electric motor 45 resting on a support bracket 46attached to the beam 41. Further, positioned above the guide 42 is adouble-action pressure piston arrangement 47, the projecting piston rod48 of which is connected, via a coupling 49, with the beam 41. The saidbeam can thus be driven with reciprocatory movement so that the circularsaw 40 cuts through the discharged web portions and parts the finishedarticle from the remainder of the web along a line passing through thecommunication passage 37.

In this way an opening is exposed at point 39, in accordance with theabove, into which a pressure medium nozzle can be inserted.

An example of how this can be used is illustrated in FIGURE 1 in whichthe reference numeral 50 indicates a stationary bracket which at itsupper end pivotally sup ports a support arm 51. The support arm ispivoted by means of a double action type pressure piston arrangement 52,the piston rod 53 of which is pivotally connected at 54 with the arm 51.Further, the free end of the arm is provided with a rearwardly directedpressure medium nozzle 55, which is connected via a pressure line 56, toa pressure medium source (not shown). The dimensions and positioning ofthe pivot arm 51 are so calculated that the nozzle 55 feels its way intothe opened passage between the webs, at the opening 39, when the armswings downwards. In normal events an immovable nozzle providessuflicient scaling in itself, against the walls of said opening when thepressure medium is caused to fiow from the nozzle into the opening. Incertan cases, however, it is expedient to turn the nozzle within theopening, during its penetration therein. The nozzle 55 in FIGURE 1 is,for this purpose, rotatably mounted on the arm 51 and can be turned bymeans of, for instance, a chain 57 driven by an electric motor 58,secured on the arm 51. The motor is suitably of the reversible type sothat the nozzle can be turned in either direction. In this connection itcan be mentioned that the connection between the nozzle and the sourceof pressure medium is suitably program controlled relative to remainingfunctions of the process.

FIGURE 5 shows an alternative to the cutting means according to FIGURE1, comprising a cutting torch 59 intended to replace the saw 40, inFIGURE 1. As can be seen from FIGURE 5 the flame 60 cuts the webs alonga transversal line 61, cutting the communication passage 37 in such away that an opening to the next, unembossed web portion is left at 62.

Another alternative cutting means is shown in FIG URE 6, said meanscomprising a shearing device having a lower, suitably stationary blade63 and an upper movable blade 64. To avoid buckling in the communicatingpassage when cutting the web, a sharp cutting point 65 is arranged onthe upper blade, the said point 65 being so positioned that it onlycomes into contact with the communicating passage 37 during the cuttingprocess.

FIGURES 7 to 9 show a few alternative designs of the pressure mediumnozzle 55 in FIGURE 1.

FIGURE 7 illustrates once again the pressure medium conduit 56 and thenozzle 55, which is mounted for rotation on the arm 51, the movement ofsaid nozzle being produced by a chain wheel 66 driven by the chain 57,shown in FIGURE 1, in either direction. The tip 67 of the nozzle itselfis provided with a screw thread type sealing flange 68 intended tosealingly close the nozzle, during rotation, to the inner walls of theexposed opening between the webs.

Another example of a nozzle is shown in FIGURE 8, wherein the body 55 ofthe nozzle is unrotatably mounted and provided with a conical nozzle tip69, around the base of which is positioned a gasket 70 intended to beurged sealingly against the edge of said opening during passage of thepressure medium therethrough.

FIGURE 9 shows substantially the same arrangement as FIGURE 8 with theexception that the gasket 70 has been omitted. The shoulder 71 forms thenecessary sealing means, and replaces the gasket means.

The aforegoing has been confined to a method in which the webs areplaced loosely one on top of the other and, in this state, operated inaccordance with the invention. In many cases, however, it may bedesirable to join the two webs intimately together. This can be effectedin a variety of ways. Thus during the process the webs can be bondedtogether by means of an adhesive or a cement. Further, heat may besupplied to the web by means of electric windings disposed in the blocks18 and 20, whereby the abutting surfaces of the webs, if for instancethey are made of plastic, can be fused together. In the case of metalwebs, for instance, the two webs may be welded together. Further, it isalso possible to coat the facing surfaces of the webs with solder, e.g.tin, and join them together by a soldering process.

According to a final alternative the process can be effected withoutjoining the webs together, the severed portions of the webs, looselypositioned one on top of the other, remaining in free superimposedrelationship after the embossing process has been carried out. The looseportions of the webs may, however, be joined together later, usingmethods suitable for the purpose.

In this connection it may be mentioned that a method has previously beensuggested wherein double-layer web material has been prepared beforehandby rolling together two metal webs. In this method, however, at leastone web has been pre-patterned using a stop weld substance, whichprevents the webs from being welded together during the rolling processat the positions treated with stop weld substance. The process accordingto the invention, however, can also be applied in this case.

To illustrate the differences which occur when carrying out the processwith webs which have been joined together from the outset, reference ismade to FIGURE 10 which to a very large extent corresponds withFIGURE 1. FIGURE 10, however, shows only one reel on which is coiled twometal webs previously welded together by rolling, between which webs acoating of material has been applied in a continuous pattern along theinner faces of the webs, the said material preventing the surfaces thustreated from being welded together during the rolling process. Thisobviates the necessity of arranging holder means on the blocks 18 and 20around the pattern when embossing. On the other hand it is important inthis context that the blocks are capable of being adjusted to adetermined distance between the two surfaces 19 and 21 so that theextent to which the pattern 73 is distended upwards can be regulated bythe same. Since, in this case it is not necessary to use engravedreaction surfaces or strips as in the case of the arrangement accordingto FIG- URE 1, the pressure medium must be prevented in some other wayfrom flowing back towards the reel 72 and embossing the continuous,pre-arranged pattern 74 located behind the blocks 18 and 20. A simplesolution to this problem is the use, in accordance with FIGURE 10, of aseparate holder means 75 suitably supported by a piston rod 76projecting from a stationary pressure piston arrangement 77. By urgingsaid holder means 75 down against the webs prior to the embossingoperation, and against an abutment means 78 positioned under said webs,it is possible to stop effectively the flow of pressure medium from thecommunication passage 79 back to the pattern 74. Embossing of thepattern 34 and forming of the communicating passage, as well as severingof the finished web portion can be effected in the same way as with thearrangement according to FIGURE 1.

The method according to the invention can be adapted with cold workingas well as with hot working of the webs.

Although the invention has been described with reference to asubstantially stationary apparatus, the material web being moved throughthe apparatus, it is also possible to arrange for the material web to bestationary and the working apparatus to be moved stepwise along thesame.

According to one alternative of the invention it is possible to workwith more than two plates on top of each other and furthermore, withseveral different patterns side by side; the webs then being divided upalong their length.

The invention is not restricted to the illustrated and describedembodiment of the same but can be varied within the scope of thefollowing claims.

What is claimed is:

1. A method for embossing repeated patterns in strip material formedfrom at least two superimposed material webs, said method comprisingintermittently advancing said strip material through an embossing zone,injecting a pressure medium between predetermined regions of adjacentwebs in said embossing zone to cause the webs to be deformed in saidregions and become embossed, pericdically cutting the strip materialafter it has passed through said embossing zone and has undergone anembossing operation, said strip material being cut to leave a portionthereof extending from said embossing zone such that the embossedregions of the already embossed strip material each provide acommunication passage extending to the regions of the strip materialwhich is next to be embossed, said pressure medium being injected to thelatter regions of the strip material to be embossed via each saidcommunicating passage.

2. A method as claimed in claim 1 wherein each communication passage isclosed to the following webs about to enter the embossing zone for atleast the length of time which the preceding webs are kept underpressure in said embossing zone.

3. A method as claimed in claim 1 comprising retaining the webs to beembossed in said embossing zone between two flat support surfaces indetermined space relationship adapted to restrict the extent to whichthe webs are deformed by the distance between said surfaces.

4. A method as claimed in claim 3 comprising varying the distancebetween the support surfaces to regulate the extent to which a patternis formed by said predetermined regions.

5. A method as claimed in claim 1 comprising retaining the portion ofthe webs to be embossed between two support surfaces capable of beingurged towards each other, at least one surface being engraved in such away that the web is forced by the pressure into the engraving andsubstantially conforms to the walls of the same.

6. A method as claimed in claim 5 wherein the support surfaces and thestrip material are moved relative to each other.

7. A method of claimed in claim 2 wherein each communicating passage isclosed by applying a press die tool to the end of the passage.

8. A method of claimed in claim 1 wherein the cutting of the stripmaterial is effected transversely of the strip material.

9. A method as claimed in claim 1 wherein the injection of the pressuremedium into the predetermined regions of adjacent webs is effected byintroducing a nozzle into each communication passage of the alreadyembossed strip material and passing the pressure medium to each nozzle.

10. A method as claimed in claim 1 wherein a portion of the stripmaterial is intermittently fed between support surfaces and permitted toremain there during the embossing operation in said embossing zone whilethe injecting and cutting of the material is effected in synchronismwith the intermittent advancement of the material web.

11. A method as claimed in claim 1 wherein the webs of the stripmaterial are arranged loosely in superimposed relation, the methodfurther comprising pressing the webs together in the regions not to beembossed prior to the injection of the pressure medium into saidpredetermined regions which are to be embossed, and interruptingcommunication between the regions to be embossed in the strip materialin said embossing zone and the subsequent strip material which has notyet entered the embossing zone.

12. A method as claimed in claim 1 wherein the webs of the stripmaterial are arranged in superimposed relationship and are bondedtogether, the method further comprising interrupting communicationbetween the regions to be embossed in the strip material in saidembossing zone and the subsequent strip material which has not yetentered the embossing zone.

13. Apparatus for embossing repeated patterns in strip materialconstituted by at least two superimposed material webs, said apparatuscomprising means for advancing the strip material intermittently throughan embossing zone, means for injecting a pressure medium, intopredetermined regions of said strip material during repeated stoppagesthereof in said embossing zone, mold means at said zone for forming adesired pattern in relief on said strip material in said regions inwhich the pressure medium is injected, means for separating embossedblanks from said strip material after the latter has passed through saidembossing zone, the latter means being positioned to separate the blanksand leave a portion of the embossed material attached to the stripmaterial in said embossing zone awaiting embossing, whereby eachembossed region in said embossed portion provides a passageway extendingto a corresponding region of the strip material in said zone awaitingembossing, said means for injecting pres sure medium to saidpredetermined regions of the strip material in said embossing zonecomprising a nozzle associated with each embossed region of the embossedportion of the strip material for supplying pressure medium thereto andthereby to said strip material in the embossing zone via the associatedpassageway and means for interrupting flow of pressure medium from saidstrip material in said embossing zone to the strip material which isnext to be introduced into said embossing zone.

14. Apparatus as claimed in claim 13 wherein said mold means comprisesmembers having opposed spaced surfaces between which the strip materialis passed, said surfaces having a groove pattern formed therein forrestricting the magnitude and extent of deformation of the webs in saidpredetermined regions in which they are embossed.

15. Apparatus as claimed in claim 14 wherein said opposed surfaces havepartly flat support surfaces and partly shaped strips projectingoutwards from at least one support surface.

16. Apparatus as claimed in claim 14 wherein said opposed surfaces havepartly fiat support surfaces and engraving portions disposed in at leastone support surface and forming said grooves.

17. A apparatus as claimed in claim 14 wherein said opposed surfaceshave flat support surfaces, the distance between which are capable ofbeing adjusted.

18. Apparatus as claimed in claim 13 wherein said means for interruptingflow of pressure medium comprises holder means including shouldersprotuding from at least one support surface to clamp the webs sealinglyagainst reaction surfaces.

19. Apparatus as claimed in claim 19 where said holder means comprisesseparately arranged and operable clamping jaws.

References Cited UNITED STATES PATENTS 2,906,006 9/1959 Neel 29157.33,031,735 5/1962 Jepson 29157.3 3,045,330 7/1962 Johnson et a1. 29-15733,052,964 9/1962 Heuer 29157.3 3,108,361 10/1963 Neel 29-157.3 3,110,09011/1963 Isbell et a1. 29157.3 3,133,517 5/1964 Brick et al. 29l57.3

CHARLES W. LANHAM, Primary Examiner M. COMBS, Assistant Examiner Us. 01.X.R.

